In the process of treating sludge dehydration, there will indeed be a mud cake "runny" phenomenon. Mud cake "runny" usually refers to the mud cake internal moisture content is higher, the texture is soft, did not form a uniform solid structure. The following are the main causes of the "runny" mud cake phenomenon:

Pharmaceutical problems:

Improper selection of agents: If the coagulant or flocculant selected is not suitable for the nature of the sludge, it may lead to poor coagulation and flocculation effect of the sludge, which affects the dehydration effect, resulting in high internal water content of the mud cake.

Insufficient or excessive amount of agent added: When the amount of agent added is insufficient, the flocculation effect of sludge may not be ideal; Excessive addition may cause the sludge to become too thick, not easy to dehydrate, and will also form a "runny" mud cake.

Equipment problem:

Insufficient pressure of the filter press: When the pressure of the filter press is set too low, it can not form an effective extrusion effect on the sludge, resulting in the water can not be fully squeezed out, thus forming a "runny" mud cake.

Filter cloth selection or cleaning problems: Improper selection of filter cloth or incomplete cleaning may also affect the dehydration effect, resulting in high water content of mud cake.

Sludge properties:

The fineness and viscosity of the sludge are too high: the fine particles and viscous substances in the sludge are difficult to be removed by conventional mechanical dehydration methods, and these substances will remain in the mud cake and increase its moisture content.

High organic matter content: The organic matter in the sludge is easy to decompose and produce water under the action of microorganisms, which will also increase the moisture content of the mud cake.

Operation problem:

Insufficient dehydration time: the dehydration time is too short, and the water in the sludge is not fully removed, which will also lead to the mud cake "runny".

Uneven feed: If the feed is uneven or too fast, it may lead to uneven distribution of sludge in the filter press, and some areas are not sufficiently dehydrated, forming a "runny" mud cake.

In order to solve the problem of "runny" mud cake, the following measures can be taken:

Optimization of agent selection: Through the experiment to determine the most suitable coagulant and flocculant types and dosage of sludge.

Adjust equipment parameters: according to the nature of the sludge and dehydration requirements to adjust the pressure, speed and other parameters of the filter press to ensure the formation of an effective extrusion of the sludge.

Improve sludge properties: by adding conditioner and other ways to improve the dewatering performance of sludge, reduce its fineness and viscosity.

Optimize the operation process: ensure that the dehydration time is sufficient, the feed is uniform, and avoid insufficient dehydration caused by too fast or too slow.

In summary, the "runny" phenomenon of mud cake in the treatment of sludge dewatering process needs to be comprehensively considered and adjusted from many aspects such as pharmaceutical, equipment, sludge properties and operation.